What do you mean? Assuming you are referring to 3th Pokémon Generation, those pokémons can be purchased from Token Store for different amount of tokens each and some of them are catchable in game. Check out the Pwo Wiki.
yes and theres also a few number of pokes from 3rd gen are catchable in the game... like bagon makuhita duscull carvanha etc ..for the rest and the most of them token store is the only option...or u can buy them from other players..